An integrated purification procedure through the LC–MS/MS-based molecular networking strategy combined with bioactive evaluation was first ushered for discovering bioactive ophiobolins from Bipolaris ...eleusines. Ophiobolins were mainly dispersed in five clusters, which were classified based on different ring systems and functional groups. Nine undescribed ophiobolins (1–6 and 9–11) and an undescribed natural product (8) along with two known analogs (7 and 12) were isolated in target. The undescribed structures were characterized by HR-ESI-MS, NMR spectra, and X-ray diffraction experiments. Compounds 3–12 exhibited strong phytotoxic effects on green foxtails by producing visible lesions, and compounds 1–10 and 12 displayed different levels of cytotoxic activities against cancer cell lines B16, Hep G2, and MCF-7, from which the possible structure–activity relationships were then suggested. The results have supported that bioactivity-guided molecular networking is an efficient strategy to expedite the discovery of undescribed bioactive natural products.
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Phytotoxicity is a significant indicator of final compost product maturity and is assessed through germination bioassays using a variety of crop seeds. In this study, the final ...composted product extracts from a mixture of different raw materials, such as swine manure (SM), biochar (BC), and sawdust (SD) were examined for their phytotoxic effects on five different commercial vegetable crop seeds.
The final composted products were procured by applying four different treatments (i.e., SM + SD + 3%BC (T1), SM:SD + 5%BC (T2), SM:SD + 10%BC (T3), and SM:SD (C) used as a control (without nanobiochar). The effect of phytotoxicity on vegetable crop seed growth was measured using GI% (germination index), RSG% (relative seed germination), and RRE% (relative root elongation) in five commercial crops, including radish (Raphanus sativus), carrot (Daucus carota), cabbage (Brassica oleracea), tomato (Lycopersicon esculentum), and napa cabbage (Brassica rapa).
In accordance with the phytotoxicity results, none of the treatment compost product extracts had any phytotoxic effect on the five commercial crop seeds, which agreed with our previous study on final product nutrient availability and manure maturity. Moreover, T3 (10% BC) showed the highest GI value compared to the other treatments, including the control.
Overall, the results confirmed that compost extract, especially 10% biochar amendment, was beneficial for commercial vegetable crops.
This study aims to determine the chemical composition of essential oil (EO) extracted from the aerial parts of Schinus molle L., as well as its phytotoxicity on germination and seedling growth ...against some invasive weed species of cereal crops and wheat (Triticum durum, cultivar Chen'S). Gas chromatography/mass spectrometry (GC-MS) identified 51 components (representing 95.26% of the total EO composition). Shyobunone (10.14%), 1-phellandrene (9.63%), α-cadinol (7.46%), δ-cadinene (7.45%), and germacrene D (7.09%) were the most abundant compounds. The effect of EO on weed species germination, root and shoot growth was moderate to strong. When 0.02% and 0.03% of the oil were applied, EO had a strong phytotoxic effect, resulting in 100% failure of Bromus rigidus germination. In addition to determining the responsible compound, the observed phytotoxicity suggestedthat S. molle essential oil could be used as an environmentally friendly biopesticide.
A strain of thiamethoxam-degrading endophyte, named TMX13, was isolated from roots of mulberry (Morus alba L.) and was identified as Enterobacter sp. Inoculating Chinese cabbage (Brassica chinensis ...L) with strain TMX13-gfp (gfp-labeled TMX13) could significantly reduce thiamethoxam residues in the aboveground part (edible portion) of the vegetable. The theoretical daily intake (TDI) of thiamethoxam via consumption of TMX13-gfp inoculated Chinese cabbage was 0.17 μg/kg body weight per day, far less than the prescribed acceptable daily intake (ADI) for this pesticide. TMX13-gfp colonization could increase the leaf chlorophyll content and plant biomass and promote the development of plant roots. Compared with the uninoculated treatment, the contents of malondialdehyde (MDA) and hydrogen peroxide (H2O2) and the activity of superoxide dismutase (SOD) in leaves of the TMX13-gfp inoculated plants decreased by 18.4%–60.2%, suggesting that TMX13-gfp colonization could alleviate the oxidative stress induced by thiamethoxam exposure. The total amounts of organic acids and amino acids in root exudates from the TMX13-gfp inoculated Chinese cabbage decreased by 9.2% and 85.2%, respectively. Results of this study lead to the conclusion that the isolated endophyte Enterobacter sp. TMX13 could reduce thiamethoxam residues in edible vegetables, promote plant growth, and alleviate the phytotoxic effects induced by thiamethoxam exposure.
The effects of the application of aqueous extracts of a selection of five traditional plants (
Murraya paniculata, Cassia tora, Amphineuron opulentum, Tithonia diversifolia
, and
Cassia alata
) were ...compared with that of synthetic acaricide in reducing the population of red spider mite (
Oligonychus coffeae
), a major tea pest, alongside their impact on natural enemies and green leaf yield. Analysis of large-scale field trials showed that all the five plants extract treatments resulted in similar yield; this was analogous to the application of synthetic acaricide. A reduction in the pest population was observed to be on par with the synthetic acaricide, with a higher number of natural enemies treated using the pesticide-plant-treated plot in comparison to the synthetic acaricide-treated plot, which indicated pesticidal plants had a lower impact on natural enemies. A phytotoxicity study on tea leaves indicated that aqueous extracts of selected plants are non-phytotoxic and do not impart any taint to the prepared tea samples. Therefore, the present investigation outlines how plant extracts used as a botanical pesticide display toxicity against red spider mite on tea plants without harming the beneficial insects, increasing the yield and avoiding any lethal consequence for the tea plants or consumers.
Developed areas of the coal industry are subjected to long-term anthropogenic impacts from the input and accumulation of overburdened coal material, containing potentially toxic heavy metals and ...metalloids (HMM). For the first time, comprehensive studies of soils and plants in the territory of the Donetsk coal basin were carried out using X-ray fluorescence, atomic absorption analysis, and electron microscopy. The observed changes in the soil redox conditions were characterized by a high sulfur content, and formations of new microphases of S-containing compounds: FeS
2
, PbFe
6
(SO
4
)
4
(OH)
12
, ZnSO
4
·
n
H
2
O, revealed the presence of technogenic salinization, increased С
org
content, and low pH contents. Exceedances of soil maximum permissible concentrations of Pb, Zn, Cu, and As in areas affected by coal dumps were apparent. As a consequence of long-term transformation of the environment with changes in properties and chemical pollution, a phytotoxic effect was revealed in
Phragmites australis
(Cav.) Trin. ex Steud, accompanied by changes in ultrastructural and organization features of roots and leaves such as increases in root diameters and thickness of leaf blades. The changes in the ultrastructure of cell organelles: a violation of the grana formation process, an increase in the number of plastoglobules, a decrease in the number of mitochondrial cristae, and a reduction in the electron density of the matrix in peroxisomes were also observed. The accumulation of large electron-dense inclusions and membrane fragments in cell vacuoles was observed. Such ultrastructural changes may indicate the existence of a
P. australis
ecotype due to its long-term adaptation to the disturbed environment.
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